LangChain Adapter

The LangChain adapter makes @pqsafe/agent-pay available as a DynamicStructuredTool in any LangChain agent. For a complete step-by-step walkthrough including agent wiring, approval gates, and production patterns, see the LangChain Integration Guide.

Quick reference

import {
  generateKeyPair,
  createSpendEnvelope,
  createSignedEnvelope,
  executeAgentPayment,
  buildLedgerRecord,
  submitToLedger,
} from '@pqsafe/agent-pay'
import { DynamicStructuredTool } from 'langchain/tools'
import { z } from 'zod'

const { secretKey } = await generateKeyPair()
const signedEnvelope = createSignedEnvelope(
  createSpendEnvelope({
    agentId: 'my-langchain-agent',
    maxAmount: 500,
    currency: 'USD',
    allowedRails: ['airwallex'],
    allowedRecipients: ['vendor.com'],
    validUntil: new Date(Date.now() + 3_600_000),
  }),
  secretKey
)

export const pqsafePayTool = new DynamicStructuredTool({
  name: 'pqsafe_pay',
  description: 'Execute a PQSafe-authorized payment. recipient: vendor.com. amount: USD ≤ 500.',
  schema: z.object({
    recipient: z.string(),
    amount: z.number(),
    memo: z.string(),
  }),
  func: async ({ recipient, amount, memo }) => {
    const result = await executeAgentPayment(signedEnvelope, { recipient, amount, memo })
    await submitToLedger(buildLedgerRecord(signedEnvelope, result))
    return `Payment ${result.status}. TX: ${result.txId}. Rail: ${result.rail}.`
  },
})

→ Full LangChain Integration Guide